Aims: Age at menopause has been proposed as a marker of aging and health. The National Health and Nutrition Examination Survey (NHANES) III, conducted from 1988-1994 provides an opportunity to examine specific medical and behavioral risk factors for early menopause. The purpose of the current study was to assess associations with menopausal status based either on menstrual cycle patterns or follicle stimulating hormone (FSH). Accomplishments: I used the Menstruation and Reproductive History Study to analyze the association between menstrual cycle patterns and several specific conditions including the association between menstrual cycle patterns and adult-onset diabetes. Increased bleeding duration was associated with increased risk of adult-onset diabetes. Early (< age 45 years) natural menopause was associated with of all-cause mortality (Cooper et al., 2000). Factors Affecting Age at Natural Menopause We published our findings from NHANES III data assessing associations between demographic, reproductive, and behavioral characteristics and menopausal status based on either menstrual cycle or elevated FSH. High body mass index (30 kg/m2 or higher) was associated with a lower likelihood of elevated FSH (OR 0.6) but this association was not seen with menstrual-based menopause. We also observed an association between exercise frequency and reduced risk of both hormonal and menstrual menopause in the NHANES data. This association has not been previously reported. Our analysis also suggested an association between alcohol use and reduced risk of menopause, but the relationships were not statistically significant. There was little evidence of associations with ethnicity, education, age at menarche, number of live births, and oral contraceptive use. I recently worked with Dr. David Savitz on an analysis of plasma levels of organochlorines (PCBs and DDE) in relation to menstrual function and age at natural menopause using data from 1407 participants in a population-based case-control study of breast cancer (the Carolina Breast Cancer Study). In a proportional hazards model of age at natural menopause, higher levels of DDE were associated with an earlier age at menopause (OR 1.5 for $ 90th percentile compared with < 50th percentile). Similar associations were seen in analyses stratified by race, lactation, and body mass index, and statistically significant associations were also seen with DDE analyzed as a continuous variable. There was little association between PCB levels and age at natural menopause.